Diffusion - clean up catching ConduitException

Summary: Ref T7123. Turns out that we might throw ConduitClientException now in proxied scenarios. For all but one callsite remove the try / catch bit and don't issue the call for SVN. For the remaining callsite, also don't issue the call for SVN but keep in the exception logic since its renders a pretty error message in the non-proxied case?

Test Plan: played around with diffusion and things looked okay.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T7123

Differential Revision: https://secure.phabricator.com/D11789

src/applications/diffusion/controller/DiffusionRepositoryController.php

@@ -374,23 +374,23 @@ final class DiffusionRepositoryController extends DiffusionController {
 
   private function buildTagListTable(DiffusionRequest $drequest) {
     $viewer = $this->getRequest()->getUser();
+    $repository = $drequest->getRepository();
 
+    switch ($repository->getVersionControlSystem()) {
+      case PhabricatorRepositoryType::REPOSITORY_TYPE_SVN:
+        // no tags in SVN
+        return null;
+    }
     $tag_limit = 15;
     $tags = array();
-    try {
-      $tags = DiffusionRepositoryTag::newFromConduit(
-        $this->callConduitWithDiffusionRequest(
-          'diffusion.tagsquery',
-          array(
-            // On the home page, we want to find tags on any branch.
-            'commit' => null,
-            'limit' => $tag_limit + 1,
-          )));
-    } catch (ConduitException $e) {
-      if ($e->getMessage() != 'ERR-UNSUPPORTED-VCS') {
-        throw $e;
-      }
-    }
+    $tags = DiffusionRepositoryTag::newFromConduit(
+      $this->callConduitWithDiffusionRequest(
+        'diffusion.tagsquery',
+        array(
+          // On the home page, we want to find tags on any branch.
+          'commit' => null,
+          'limit' => $tag_limit + 1,
+        )));
 
     if (!$tags) {
       return null;
@@ -402,7 +402,7 @@ final class DiffusionRepositoryController extends DiffusionController {
     $commits = id(new DiffusionCommitQuery())
       ->setViewer($viewer)
       ->withIdentifiers(mpull($tags, 'getCommitIdentifier'))
-      ->withRepository($drequest->getRepository())
+      ->withRepository($repository)
       ->needCommitData(true)
       ->execute();